Researchers from Loyola University in Chicago have discovered that normal urine in healthy people can contain bacteria. It is a commonly held belief that normal urine is sterile and the presence of bacteria in urine must be an abnormal finding which could contribute to urinary symptoms. Using very careful collection techniques and very sensitive ways of detecting bacteria, these researchers in Chicago have demonstrated that normal urine can contact bacteria. The other side of the coin here is that traditional ways of identifying bacteria in the urine may be insufficiently sensitive to pick up all types of urine infection. We have known for some time that some patients with the typical symptoms of a urine infection can get better with antibiotics even when bacteria cannot be identified. This recent study demonstrates that this may be because there has been bacteria in the urine all along but we have just been unable to find them.